Method ( 100 ) implemented through a distributed computer
system (2 ) to dynamically determine at least one travel or stay
risk index in at least one geographical area, comprising the steps of : - defining ( 101 ) a plurality of risk categories, each
risk category corresponding to a type of risk to which a person may be exposed when travelling or staying in said geographical area; - defining ( 102 ) for each
risk category a plurality of keywords semantically related to the
risk category and storing said plurality of keywords in a
data structure; - for each risk category, extracting ( 103 ) first risk data by consulting informative websites and
social media and carrying out a computer
sentiment analysis of first textual contents published in, or associated with, a first relatively long time period on said informative websites and
social media, where the first textual contents concern and / or mention said geographical area and are selected using the keywords semantically related to the risk category; - determining ( 104 ) a basic
risk index associated with the geographical area starting from the first risk data; - receiving or generating a ( 106) request to determine a. n instantaneous
risk index associated with the geographical area; - for each risk category, extracting ( 107 ) second risk data by consulting informative websites and
social media and carrying out a computer
sentiment analysis of second textual contents published in, or associated with, a second relatively short time period on said informative websites and social media, where the second textual contents concern and / or mention said geographical area and are selected using the keywords semantically related to the risk category; - determining ( 108 ) an instantaneous risk index associated with the geographical area starting from the second risk data; - comparing ( 109 ) the instantaneous risk index and the basic risk index; generate and send ( 110 ) a notification and / or
control signal if from the comparing step it is found that the instantaneous risk index is higher than the basic risk index